Power BI is a business analytics service and data visualization tool developed by Microsoft. It allows users to connect to various data sources, transform and clean the data, and create interactive reports and dashboards for data analysis and decision-making.

Key features of Power BI include:

1. Data Connectivity: Power BI can connect to a wide range of data sources, including Excel spreadsheets, databases, cloud services, and online services, among others.

2. Data Transformation: The tool provides capabilities to transform and shape the data using Power Query Editor, allowing users to clean, filter, and combine data from multiple sources.

3. Data Modeling: Power BI enables users to build relationships between different data tables, creating a data model that helps in creating insightful visualizations.

4. Interactive Visualizations: Users can create a variety of interactive charts, graphs, and other visualizations to represent data in a meaningful way.

5. Dashboards and Reports: Power BI allows users to build interactive and customizable dashboards and reports that can be shared with others in the organization or embedded in web applications.

6. Natural Language Queries: Power BI supports natural language queries, allowing users to ask questions about their data and receive relevant visualizations as answers.

7. Collaboration and Sharing: Users can collaborate with others by sharing their reports and dashboards with colleagues or stakeholders. Power BI also provides the ability to publish reports to the Power BI service or export them to various formats like PDF or PowerPoint.

8. Mobile Access: Power BI offers mobile apps for iOS and Android devices, enabling users to access their reports and dashboards on the go.